Paper tape punch and reader

ABSTRACT

A combination paper tape punch and reader having a bi-directional stepping tape transport controlled by a continuously oscillating magnetically activated pawl. A further improvement is a punch interposer geometry allowing for easy removal of the punch and die. A single motor and timing signal is used for both punch and reader tape transports.

CROSS-REFERENCE TO RELATED APPLICATION

This invention is not disclosed in any co-pending application for apatent or any issued patent.

FIELD OF INVENTION

Coded paper tape has been used since approximately 1900 toelectronically convey messages and to control the operation of numerousmachines.

The most common paper tape today, containing eight code holes and acontinuous line of transport holes is the ASCII tape. While it isanticipated that the current invention will have its principalapplication here, the invention is not so limited.

The punch and reader of this invention and certain machines of the priorart is further adapted to receive assynchronous signals andsynchronously punch and read the paper tape. DESCRIPTION OF PRIOR ART

The most widely used punches and readers today are the Models 32 and 33ASR units manufactured by the Teletype Corporation, and introduced about1960. These machines operate at a rate of ten characters per second.

Another widely used punch and reader is manufactured by the LittonCorporation and operates up to 60 characters per second.

SUMMARY OF THE INVENTION

This invention greatly simplifies the mechanisms of paper tape punchesand readers and thereby improves the reliability and reduces the initialcost and further reduces the service cost of paper tape punches andreaders. As indicated above, these machines have operatingspecifications controlled by industry wide standards and thereforeoperational differences are neither desired nor permitted.

The first improvement is the bi-directional stepping mechanism. Thearrangement of the oscillating pawl minimizes the inertia and reducesthe number of parts. The same mechanism is used for tape transport ineither direction.

The second improvement is the punch interposer armature geometry whichacts as a mechanical memory minimizing energy consumption. This newinterposer design both drives the punch into the paper tape andwithdraws the punch from the paper tape. The design allows the bail tomerely pivot instead of sliding. Furthermore, the design allows for easyremoval of the punch and die assembly.

The third improvement is the combination of the paper tape punch andreader which uses a single motor and timing signal, eliminating the costof duplicate mechanisms.

DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of the punch and reader.

FIG. 2 is a vertical sectional view taken on lines 2--2 of FIG. 1.

FIG. 3 is a vertical transverse sectional view of the punch mechanismtaken on lines 3--3 of FIG. 2.

FIG. 4 is a fragmentary side view of the magnet, interposer and punchshown in FIG. 2 with the punch withdrawn and the interposer engaged withthe bail shaft which is in the lowered position.

FIG. 5 is the same view as FIG. 4 except that the interposer and punchhas been raised by the bail shaft to punch the paper tape.

FIG. 6 is the same view as FIG. 5 except the punch and interposer havebeen withdrawn by the lowered bail shaft and the interposer has thenbeen tilted out of engagement with the bail shaft.

FIG. 7 is the same view as FIG. 6 except the bail shaft has risenwithout contacting the interposer, which holds the punch in thewithdrawn position.

FIG. 8 is a side view of the tape transport for the punch or reader.

FIG. 9 is a sectional view of the transport taken on lines 9--9 of FIG.8.

FIG. 10 is an exploded schematic view of the punch or reader transport.

STRUCTURE OF DISCLOSED EMBODIMENT

The paper tape punch and reader has seven principal assemblies. Mountedon the housing 20 is the punch assembly 21, the reader assembly 22, thedrive or power assembly 23, the punch magnet assembly 24, the punchinterposer assembly 25, a pair of transport assemblies 26 and rockerassemblies 27, one of each associated with the punch assembly and theother of each associated with the reader assembly.

The punch assembly 21, as best shown in FIGS. 2 and 3, consists of aconventional die block 31, punch guide block 32 containing theconventionally spaced and sized set of eight code punch pins 33 and onetransport punch pin 34. A conventional chute 35 is shown for removingthe punched paper chad.

As best shown in FIG. 3, at the bottom of each of the punch pins 33 and34 is a finger 36 cooperating with the interposer punch pin notch 64.

The reader assembly 22 is, with one exception, conventional and willtherefore not further be described in this application. That exceptionis the tape transport assembly 26 and rocker assembly 27 whosecounterpart is described in connection with the punch assembly below.

The drive assembly 23 comprises the conventional electric motor 40 andbelt drive 41 operating the main drive shaft 42. Three eccentrics aremounted on the main drive shaft. At the left, as shown in FIG. 3, ispunch tape transport eccentric 44, in the center is punch bail eccentric43 and on the right is reader tape transport eccentric 45.

As most clearly shown in FIG. 2, the eccentrics cause movement of punchtape transport connecting rod or link 47, and mounted behind that, punchbail connecting link 46 and mounted behind that reader tape transportconnecting link 48.

The punch bail connecting link 46 causes the punch bail crank arm 50 torotate around bail shaft 49, thus reciprocating the end of punch bail 51in a continuous oscillating motion.

The drive shaft also has attached to it a conventional flywheel 52 and ashutter 53 co-operating with an opto-electronic transducer 54.

The punch interposer assembly 25 includes a set of nine spaced punchinterposers 60, each engaging with one of the eight code punch pins 33and single transport punch pin 34. Each of the interposers rests on androtates on a common interposer shaft 61. Each interposer 60 is biased ina counterclockwise direction by its associated interposer spring 62. Theinterposer is prevented from further counterclockwise movement bycontacting either the bail 51 in its interposer notch 63 as shown inFIG. 2, 4 and 5 or by interposer finger 65 contacting the lower edge ofarmature slot 75 as shown in FIGS. 6 and 7.

The punch magnet assembly 24 comprises a set of four upper magnets 70and five lower magnets 71. Associated with the magnets are a set of fourupper armatures 72 and a set of five lower armatures 73. The uppermagnet armatures 72 are biased counterclockwise by the upper set ofarmature return springs 74 and the lower magnet armature 73 are biasedclockwise by the lower set of armature return springs 74. The movementof the armatures are limited by contact with interposer fingers 65associated with each armature. Each of the magnets is selectivelyenergized to cause the associated punch pin to operate during thefollowing cycle of the punch.

Each of the tape transport assemblies 26 are identical, although mountedon opposite sides of the punch and the reader as shown in FIG. 1. Asprocket wheel 80 engages the tape, indexing the tape over the lineardistance of one hole spacing.

The sprocket is mounted on and rotationally controlled by sprocket shaft81. Rocker frame 91 is freely journaled on sprocket shaft 81, as issquare tooth wheel 85. Rotation of shaft 81 is caused by, in turn,oscillation rocker frame 91, selective de-energization of pawl 92engaging square tooth wheel 85 which is fixed to shaft clamp 87. Shaftclamp 87 is mounted on the sprocket shaft by screw 88 and its angularposition is adjusted by stub 86 of square tooth wheel 85 fitting in itsenlarged upper aperture, and being positioned by adjusting screws 89.

Square tooth wheel 85 is held in position by detent arm 82 and detentroller 83 whose position over one index width can be adjusted by detenteccentric 84.

The rocker assembly 27 includes rocker pivot 90 attached to connectinglink 47 or 48, and causing the rocker frame 91 to reciprocate angularlyaround sprocket shaft 81.

Mounted on the rocker frame are a pair of coils 97, coil posts 94, apawl pivot post 93, on which is mounted the transport pawl 92, which isthe armature for coils 97. The transport pawl contains a drive tooth 95co-operating with the indentations or notches of square tooth wheel 85.The transport pawl is biased away from the coil posts by pawl spring 96.

MODE OF OPERATION

The conventional code signal for the eight hole paper tape is a stringof electrical pulses creating a potential 256 element code. Thesesignals are received assynchronously or randomly and are punchedsynchronously. The reader may operate independently of the punch.

A typical application is for a manually operated keyboard to operate thepunch, relatively slowly and irregularly. At selected times, the readerwill operate to rapidly transmit a length of the tape which has beenpunched.

The electric motor 40 runs continuously during operation, rotating driveshaft 42 by belt 41. The drive shaft turns eccentrics 44, 43 and 45,thus continuously reciprocating punch tape transport link 47, punch baillink 46, and reader transport link 48.

A fly wheel 52 provides mass to minimize the transient shock loadscaused by the intermittent operation of the punches and the tapetransports.

The electro-optical transducer 54 and shutter 53 provide a timing signalwhich goes on at 0° and off at 180° of each cycle to control the variousfunctions.

An incoming punch signal is initially stored in a buffer which is readonce each cycle. A machine designed to respond to incoming signals of upto 30 cycles per second will operate at 33 cycles to eventually unloadthe buffer.

FIG. 4 shows the bail 51 at the bottom of its stroke and armature 72energized or withdrawn from interposer finger 65. The interposer asshown has rotated under influence of spring 62 counterclockwise to allowinterposer notch 63 to engage the tip of the bail 51.

In FIG. 5, the bail 51 has driven interposer 60 upward, driving thepunch pin into the paper tape. The magnet 70 has meanwhile de-energized,allowing the armature 72 to rotate counterclockwise. The tip ofinterposer finger 65 has slid upwardly in armature slot 75.

FIG. 6 illustrates the condition where the shown punch should notoperate during the next cycle. The magnet continues to be de-energizedand the armature is biased counterclockwise as shown in FIG. 5. The bail51 as shown in FIG. 6 has moved to its downward position, pushing downthe interposer 60 and withdrawing punch pin 34 from the paper tape. Atthe same time, the interposer is rocked clockwise by the engagement ofinterposer finger 65 against the lower edge of armature slot 75.

FIG. 7 shows the quiescent state of the armature 72, interposer 60 andpunch pin 34 as the bail freely oscillates upwardly, missing theinterposer.

The signal to any magnet need be only large enough to rotate itsarmature against its biasing spring. The signal need be only long enoughto allow the interposer finger 65 to clear the bottom edge of slot 75.Specifically, the magnet need not be energized during any portion of theupward bail shaft movement during a punching operation. I term thisfeature a mechanical memory. It serves to substantially reduce the powerrequirement thus reducing the size of electronic components and cost ofthe machine.

During penetration of the punch pins, the tape must be held stationaryand must index one space during the period the punches are in theirwithdrawn position.

The tape is held stationary by detent roller 83 which is spring loadedagainst square tooth wheel 85. Since the standard specifications for thedistances between the rows of holes is very precise, a fine adjustmentis provided. The movement of square tooth wheel 85 is governed by therotation of the rocker frame 91. Adjustment between square tooth wheel85 and sprocket shaft 81 is therefore provided. Shaft clamp 87 isjournaled on both sprocket shaft 81 and stub 86 of wheel 85. Screw 88 istightened and the angular position of sprocket shaft 81 is adjusted bythe setting of adjusting screws 89 in the enlarged aperture of shaft 87clamp which loosely fits around stub 86.

Prior to the above adjustment, the position of detent roller 83 isadjusted. Detent eccentric 84 is conventional and allows adjustment ofarm 82. A spring, not shown, biases arm 82 against square tooth wheel85.

The tape transport cycle is controlled by the rocker assembly andultimately by the tape transport eccentric 44 which is positionedrelative to the punch bail eccentric 43 so that the rocker motion isoffset one quarter cycle, to move the tape forward during the withdrawnhalf of the punch cycle. As rocker frame approaches one limit, thecurrent in coils 97 is turned off, allowing pawl 92 to rotate, insertingtooth 95 into the associated indentation or notch of square tooth wheel85. At the end of the cycle, the tooth is withdrawn and the wheel isheld in position by detent roller 83.

The reverse stepping of the tape is accomplished by having the toothengage during the opposite travel of rocker frame 91. This occurs duringthe portion of the cycle the punching would normally be extended and areof course all withdrawn by the above-described armatures holding theinterposers out of engagement.

The positioning of coils 97 as shown is unusual. The plane of rotationof the pawl 92 is normal to the axis of the coils. This allows therequired magnetic flux to be generated while bringing the mass of thecoils nearer the center of rotation, thus reducing the moment ofinertia, force required, and vibrations generated during operation ofthe rocker assembly.

Although the present invention has been described with reference to aparticular embodiment thereof, it should be understood that thoseskilled in the art may make many other modifications and embodimentsthereof which will fall within the spirit and scope of the principles ofthis invention.

What is claimed as new and desired to be secured by patent of the UnitedStates is:
 1. A paper tape transport for transforming continuous rotarymotion of a drive shaft into selectively intermittent sinusoidalbi-directional movement of the paper tape comprising:(a) a continuouslyreciprocating driving link; (b) a continuously oscillating assemblydriven by said link over an arc equivalent to the linear hole spacing onthe paper tape; (c) a selectively energizable magnet mounted on saidoscillating assembly; (d) a pawl mounted on the oscillating assembly andcontrolled by said magnet, the pawl containing a driving tooth; (e) abi-directional driving wheel engageable with said tooth; (f) a tapetransport sprocket operatively connected to said driving wheel andengaging said paper tape; and (g) means to restrain movement of saidsprocket when no signal is received by said magnet to engage said toothof said armature.
 2. The paper tape transport of claim 1 in which thebi-directional driving wheel is a square tooth wheel.
 3. The paper tapetransport of claim 1 in which the plane of rotation of the pawl isnormal to the axis of the magnet coil.